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Redirected from QoS-enabled switch A multilayer switch (MLS) is a computer networking device, that switches on OSI layer 2 like an ordinary network switch - and provides extra functions on higher OSI layers.

MultiLayer Switch (MLS) - OSI layer 3 and/or 4

A Multilayer Switch (MLS) can priorties packets by the 6 bits in IP DSCP (differentiated services CodePoint). These 6 bits was used in the "old days" for Type of Service (ToS).

The following 4 mappings are normally available in a MLS:

• From OSI layer 2, 3 og 4 to IP DSCP (if IP packet) and/or VLAN IEEE 802.1p.
• From VLAN IEEE 802.1p to IP DSCP.
• From IP DSCP to VLAN IEEE 802.1p.
• From VLAN IEEE 802.1p to port queue.

Many MLS implements QoS differentiated services and/or integrated services in hardware.

Some MLS are also able to route between VLAN and/or ports like a common router. The routing are normally as quick as switching (with wirespeed).

Layer 7 switch, web-switch, content-switch

Some switches can use up to OSI layer 7 packet information, they are called layer 7 switches, content-switch or web-switch.

Some of the applications areas are load-balancing among HTTP, HTTPS and/or VPN servers. Load-balancing can be made by using NAT. Some of the layer 7 switches can NAT at wirespeed.

Elsewhere

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